Hearing Loss.
Hearing loss effects nearly 40 million Americans, but many individuals suffering from hearing loss or other hearing-related disorders do not seek clinical help because of stigma, financial constraints or other obstacles, and many people are unaware of their hearing impairment.
Even people fitted with hearing aids show limited success because the devices do not account for the detrimental neural changes induced by hearing loss that prevent the user from maximally exploiting low-level speech cues, such as subtle changes in frequency and timing.
Impaired hearing desensitizes the cortex to hearing-loss frequencies and degrades its ability to distinguish auditory input. These cognitive deficits disrupt higher-level auditory processing like phoneme discrimination, ultimately impairing the hearing-impaired individual's ability to engage in and remember conversations.
Hearing aids do not correct this pathological neural function because the cortex must be trained to properly discriminate and utilize the frequencies amplified by the aid along with other auditory information lost from degraded input.
Auditory perceptual training can reverse the pathological plasticity associated with hearing loss by training the individual to make the necessary temporal, intensity and frequency discriminations required for healthy hearing abilities. As these discriminations are fundamental to phoneme processing, such training can improve speech perception. In fact, phoneme discrimination training has been shown to improve speech perception in hearing-impaired individuals beyond the benefit of a hearing-aid alone. Although previous art has shown that auditory perceptual training can improve speech perception in hearing-impaired individuals, such training has not been tailored to individuals' personal hearing needs.
There is a need for individually-tailored auditory perceptual training. There is a concomitant need for practical automated systems and methods for tailoring auditory perceptual training to an individual.
Audiometry.
There are many methods of audiometry for diagnosing hearing loss. But current clinical audiometric methods are not able to be implemented on personal computers operable by a layperson; i.e., the sufferer of hearing loss. Current clinical audiometric devices require a trained audiologist to operate and interpret the test results in the form of an audiogram. Worse, apparently similar audiograms may permit multiple interpretations because of technical variations in audiometric methods and test subject idiosyncrasies. These and other complications must be overcome to make audiometric methods simple enough for the sufferer to use themselves, and accessible enough to be used on their own device (such as a personal computer via the internet).
There are additional obstacles to developing a layperson-operable audiometric device. The sound output by sound cards and headphones varies from one device to another. Ensuring accurate sound pressure levels across the range of tested frequencies requires calibration of the sound output to compensate for distinct frequency responses of the computer's sound card and the headphones used during the test. Also, sine tones commonly presented in audiometry can produce harmonic distortion when presented at intense levels. Additionally, personal computers produce noise that may interfere with the user's performance.
Also, current audiometric methods focus only on quantifying hearing thresholds. We are aware of no prior art audiometers that inform perceptual training software as to what kinds of sound discriminations would be most useful for the user.